What Are STCs and Why Do They Matter?

Small-scale Technology Certificates (STCs) are one of the most misunderstood parts of going solar in Australia. Here's what you need to know.

What are STCs?

STCs are a federal government incentive under the Small-scale Renewable Energy Scheme (SRES). When you install a solar system, it's deemed to generate a certain number of certificates based on the amount of electricity it will produce over its lifetime (up to 2030).

How the value is calculated

The number of STCs your system generates depends on three things: - System size — larger systems generate more certificates - Your location (zone) — northern Australia gets more sun, so generates more STCs - Years remaining — the scheme ends in 2030, so STCs decrease each year

Australia is divided into 4 STC zones. Zone 1 (NT) generates the most, Zone 4 (TAS) the least.

What are they worth?

Each STC has a market value that fluctuates, typically between $33–$40. A standard 6.6kW system might generate 50–70 STCs depending on location, worth roughly $1,650–$2,800.

How installers handle them

In almost all cases, your installer will claim the STCs on your behalf in exchange for a "point of sale discount" — meaning they reduce your upfront cost. This is legal and standard practice. However, they must disclose: - That they are claiming the STCs - The number of STCs being claimed - The value being assigned to them

What to do if STCs aren't mentioned

If your solar quote doesn't mention STCs at all, this is a red flag. Ask your installer directly: "How are STCs being handled in this quote?" Get the answer in writing.

Try the calculator below

Use our STC estimator to see what your system might be worth: